it really works! i got my newton connected using a serial to usb adapter [with some drivers installed] under os x 10.4.10 to the powerpc imac i use at work. then,
with newten i was able to upgrade my newton messagepad 110 from os 1.2 to 1.3, install battleship, a guitar tuner and a newton book version of the communist manifesto. this is a very reliable package installer and i experienced no issues what-so-ever.